We're just one game into the Western Conference Finals and already it might be the most interesting series in terms of matchups. The outcome of Game 1 hinged largely on a subject that was prominently featured in our series preview: smallball. As expected, Scott Brooks went into the game thinking that the Oklahoma City Thunder's best chance of winning was to go small and speed up the game. Backup center Nazr Mohammed never got off the bench, as Brooks instead favored an ultra-small lineup with Daequan Cook and Thabo Sefolosha at forward next to Nick Collison during the second quarter. After halftime, Brooks stretched out Kevin Durant, who played all 24 minutes--the last 16 of them at power forward.

Through most of the first three quarters, Gregg Popovich elected not to match up small with the Thunder, a strategy that met with mixed results. Popovich changed course with 3:15 left in the third quarter, inserting Gary Neal for Matt Bonner, putting first Kawhi Leonard and (moments later) Stephen Jackson at the four spot. According to BasketballValue.com, Jackson played about 37 minutes of power forward for the Spurs during the regular season and 10 more in the playoffs, entirely in garbage time. Still, Popovich confidently went to the lineup with four wings plus Tiago Splitter, and it changed the game.

With so many shooters on the floor, San Antonio spaced out Oklahoma City and opened up driving lanes and pick-and-roll opportunities. Splitter scored two easy buckets as a roll man and got to the free throw line twice more (making just one of his four attempts and throwing up an unexpected airball) before giving way to Tm Duncan. With Tony Parker stepping in at the point, joined by Jackson, Neal and Manu Ginobili, Popovich had his finishing lineup. The group outscored the Thunder 27-16 over the next eight minutes.

Besides the offensive weaponry, the small lineup worked so well for the Spurs because of the difficult choices it forced Brooks to make about his lone big man. Serge Ibaka briefly played the middle during the second quarter, but predictably struggled to defend Duncan one-on-one. Ibaka has made progress in this regard but lacks the savvy, strength and experience to defend Duncan, who went right around him for a layup. Instead, Brooks chose to finish with Kendrick Perkins and leave Ibaka on the bench for the entire fourth quarter. That caused two problems. First, San Antonio is essentially ignoring Perkins on defense in favor of selling out on Durant and Russell Westbrook, especially in the pick-and-roll. Second, while superior as a post defender, Perkins is less effective at altering shots than Ibaka, the league's leading shot blocker. Perkins was rarely in position to contest as the Spurs wore a path to the rim during the fourth quarter.

A similar offense-defense dilemma was playing out on the wing. The small lineup allowed Brooks to get more minutes for an improbably hot Derek Fisher, who made all six of his shot attempts. However, playing Fisher forced James Harden to defend Ginobili, sapping his energy for offense and giving Ginobili more opportunities on offense. So Thabo Sefolosha briefly replaced Fisher, giving Oklahoma City one less shooter on the floor.

The choices aren't nearly as difficult for Popovich because San Antonio's role players contribute at both ends. Jackson took over defending Durant for the final period, holding him to six points, all at the foul line. Jackson's physical style helped him deny Durant the basketball and keep him from getting to his favored spots. In addition to scoring 12 points on nine shooting possessions, Neal took a series of charges at the defensive end. Both reserves stepped up big on a night where starting wings Leonard and Danny Green were ineffective, shooting a combined 3-of-15 from the field.

No matter what, Brooks is going to have to sacrifice something, but I think the Thunder coaching staff needs to revisit the notion that smallball is an advantage over the Spurs. It may have worked against the regular season, but San Antonio's lineup is now substantially different with the addition of a healthy Ginobili, as well as Jackson. The Spurs go much deeper on the wing than Oklahoma City, so going small puts the Thunder at a talent deficit.

Maybe things would be different with Ibaka in the middle--or even Collison, the team's most well-rounded big man--but in practice Oklahoma City's bigger starting lineup was its most effective option. With Ibaka and Perkins on the floor together, the Thunder outscored San Antonio by seven points in 19 minutes. That has something to do with Ginobili not being part of the starting lineup, but clearly playing big did not hurt Oklahoma City. It's worth giving that unit a shot during the fourth quarter.

Kevin Pelton is an author of Basketball Prospectus.
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